1. Field of the Invention
The invention relates to a pair of binoculars, a telescope of the like, comprising a protective lens cap articulated to a front of the lens.
2. Background Art
Conventional protective lens caps of the generic type are usually designed in such a way that they are not at all secured to the casing and, upon removal of the caps, they easily get lost and must be kept carefully, or they are articulated to the edge of the lens by a so-called integral hinge. This hinge precludes the protective caps from getting lost; however, they will flap in the wind and whenever the binoculars are moved, directly interfering with any observation or indirectly interfering by reflections.
It is an object of the invention to provide an optical instrument of the type mentioned at the outset with protective lens caps in such a way that these protective lens caps cannot get lost during observation and will definitely not impair, or interfere with, observation.
According to the invention, this object is attained in that a pivot joint is formed between the edge of the lens and the protective lens cap, in use having a substantially horizontal pivot axis and a substantially vertical pivot axis.
The design according to the invention enables the protective lens cap to be swung upwards in a manner known per se about a substantially horizontal pivot axis, and then, by rotation about the substantially vertical pivot axis in particular by 180xc2x0, to be swivelled with the inside turned towards a user""s face, and then to be folded down on the top or bottom of the optical instrument where it is reliably secured and does not interfere with observation.
In keeping with a first embodiment according to the invention, it is provided that the pivot joint arrangement, in the vicinity of the edge of the lens, comprises a substantially horizontal pivot joint and, further outwards, a substantially vertical pivot joint i.e., two successive, separate pivot joints.
In keeping with an alternative embodiment, provision is made for the pivot joint arrangement to be a ball-and-socket joint so that the horizontal and the vertical pivot axes combine and are comprised in a single joint arrangement, which ensures highly economic manufacture and advantageous final assembly by reason of the snap-in locking that is feasible in such a ball-and-socket joint.
By advantage, the pivot joint arrangement may further be embodied for defined internal friction or locking such that the protective lens cap can be positioned in a stable stop position i.e., no special locking mechanisms are needed on the top surface of the casing, keeping the protective caps in the stop position folded down on the top surface.
By advantage, the protective lens caps, when removed from the lens and swung out, serve as a support for the optical instrument when it is put down, this offering another possibility of use of the caps which reliably preclude any damages to the instrument when it is put down and make it easier to lift the instrument by producing a distance from where it is put down.
Details of the invention will become apparent from the ensuing description of a preferred embodiment, taken in conjunction with the drawing.